Light-Emitting Diode,LED is a two terminal Electronic Components. Apply enough voltage between two terminal of LED to emitting color. Different material and Manufacture process decide emitting light color and most of electronic characteristic. Each LED with certain material and manufacture process emitting one kind of color. If product need specific emitting color or need to change color. We need use Red ,Green ,Blue LED with RGB color model to create color we need. This paragraph don’t cover about RGB color model. We only discuss how to choose the lowest-cost colored LED for your product.
Why product designer need lowest-cost colored LED?
Theoretically, Any LED emitting color can be made by adjust the material and manufacture process. However, Production cost will be extermaly high to made every emitting color for LED factory. Therefore, LED factory choose most use colored LED into mass production in order to reduce production cost and get enough profit.
You can image LED as a Light bulb. When Light Bulb apply correct electricity, Light Bulb start emitting light. The Color, Brightness were decide when the Light Bulb was made. In order to cut cost ,factory choose a series of LED with most used color and brightness. RGB Light bulb were use for specific color application ,instead of create a specific color. If you choose existing series of LED color for your product, you can cut of the total cost for your product.
How to express color in LED?
it’s might be a hard job to express a certain color with other. For Example, The Blue color show in below picture.
Everyone might have different option about this blue ,might be sky blue, water blue ,or even Ferrari blue. Other factor like shown in different monitor, print in different product.
Some company develop Color Card system, For example,Pantone color system, to fill the designer’s need to make sure the color of product will be the same throughout design flow.
For Light-Emitting Diode, We use the wavelength of Emitting light to express the Emitting color, Following visible light spectrum, Classify visible to seven color : Red, Orange, Yellow, Green, Cyan, Blue, Violet.
Most use LED Emiting color for LED maker.
The Most used Emiting color for LED are : Blue, Amber, Orange Red, Red, Yellow, Yellow Green, Pure Green. Following table show the name and color.
Some time, Orange Red might be call Red Orange color. Two of the expression means same color. The color between Orange and Red color. On the other hand, it’s seldom to call Yellow green color as green yellow color. White color is another most use LED emitting color. But their are too much detail about White color, we will discuss in this article.
If you need the other color then the table above, It’s need customization LED with higher price. That’s why we need to choice right color for low budget product design.
Wavelength range for 7 most use LED Emitting Color
Each LED Display use different LED from different LED. Datasheet only show the LED emitting color specification.
Different Wavelength range for each LED Emitting Color
For each LED maker, They might have different Wavelength range for same color, For example, Amber Color in OPS-S5620(1)SA and OPD-M25710(1)LA have Different Wavelength range. you should check every time when application need exact colored LED.
This article make a brief introduction about 7 most used LED emitting color. and cover about ,How LED define color , and how every LED factory define their color. Product designer can choose the lowset-cost LED color from the very early stage of design flow.